Thank you for your question, and thanks for using JustAnswer.com. It's true that a lot of China's growth and stability are pumped up by the US economy
they are one of the largest holders of our debt, but we also are a major source of exports for their country. So, if China does something drastic like dump their debt with us, they would also be hurting themselves because their growth depends on exports to the US (among other things).
If the debt ceiling is not raised, the US would run out of money to pay its bills. But, they would still be able to spend the amount of money that they bring in in taxes.
The US would have to prioritize their payments -decide who to pay and who to defer payment until later.
Everything you need to know about the debt ceiling can be found in an article, HERE
To be honest, we are walking a fine line. However, I doubt that Congress and the President will allow the country to hit the debt ceiling.
Allowing that to happen could cause a recession similar to the recession that we saw in 2008. I don't think the government would want to be the cause of that.
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